Conventionally, there has been a sunroof apparatus that includes a front panel retractably opening/closing a front portion of a roof opening formed in a roof of a vehicle, a rear panel retractably opening/closing a rear portion of the roof opening, a front slider actuating the front panel by moving back and forth, and a rear slider actuating the rear panel by moving back and forth (see Patent Literature 1). In this sunroof apparatus, a pair of front and rear lift guide grooves are formed in a rear lifter attached to a lower surface side of the rear panel, and each of the lift guide grooves is formed to be a rearward up-grade inclined groove.
Meanwhile, supporting portions for supporting the rear panel are provided in the front and rear portions of the rear slider. In a state that the rear panel is positioned in a close position closing the rear portion of the roof opening, the supporting portion provided in the front portion of the rear slider is positioned at a front end of the front lift guide groove and the supporting portion provided in the rear portion of the rear slider is positioned at a front end of the rear lift guide groove.
From this state, when the rear slider is moved backward, the supporting portion in the front portion is moved backward within the front lift guide groove and the supporting portion in the rear portion is moved backward within the rear lift guide groove so that the rear portion of the rear panel is lowered.